In the Swedish patent application 8704883-1 and following international patent applications e.g. PCT- SE88-00653 there are shown methods to develop pictures and texts by means of pigment particles on an information carrier, directly from computer generated electric signals, without need for these signals to be intermediately stored at a temporary conversion to light energy, which is the case in photo conductive printers e.g. laser printers. These tasks have been solved by bringing the information carrier into electric cooperation with at least one screen or grid formed matrix, preferably an electrode matrix, which by control in accordance to the desired pattern configuration at least partly opens and closes passages through the matrix by galvanic connection of this to at least one voltage source, and that through thus opened passages an electric field is exposed for attraction of the pigment particles towards the information carrier.
This method (in the following called the EMS -Concept), as it is described in the above patent applications, however may imply that the printing produced does not show high quality enough. This is the fact in particular in embodiments with the multiple line electrode matrix according to the invention. It has been verified that it is difficult to "address" a single passage or mesh in the electrode matrix without influencing surrounding passages wholly or partially and hereby cause undesired blacking dots on the background of the printed paper. This phenomenon in the following is called cross coupling between passages.
Cross coupling between passages is not limited to the EMS -Concept but is found, wholly or partially, in several electrographic printing concepts where passages are created in an electric way, e.g. GB 2108432A.
What is common to all problems and drawbacks in the state of art is the printing quality and thereby the readability being affected in a negative sense with reduced competitiveness and low value for the user as a result.